David Hughes is the Daily Telegraph's chief leader writer. He has been covering British politics for 30 years.

Mandelson takes on the Brown/Balls axis

Remember John Prescott's tectonic plates (or were they dinner plates?). When he said they were moving in 2004, he was commenting on the latest Brown/Blair nonsense but his intervention, in retrospect, started the long slow process of Tony Blair's departure from Downing Street three years later. Well, the plates are moving again. Our story this morning revealing tensions between Gordon Brown and Lord Mandelson has immense implications. As Andy Porter points out, Mandy is the man who kept Brown in place during June's botched Cabinet coup. His reward? To get squeezed out of the Brown inner circle. Big mistake, Gordon. A scorned Peter Mandelson is a dangerous creature. What will particularly irritate the First Secretary of State is the fact that Ed Balls has resumed his old role as Brown's most trusted adviser. The ideological gulf between Balls and Mandy – they are Old and New Labour incarnate – is as nothing when compared to the personal animosity. Not to put too fine a point on it, they loathe each other. This new split makes the Cabinet potentially very unstable. We have already had a statement of intent from Mandelson this morning with his warning of deep cuts in higher education funding. What could be more provocoative for the Brown/Balls axis and their mantra of Labour investment against Tory cuts than to see Mandy pushing through education cuts? This could get very lively indeed.